Bruce Allardice has traced and charted the growth of base ball in the US from 1859 to 1870 as it is presently captured on the PBall site. See http://protoball.org/The_Spread_of_Base_Ball,_1859_-_1870. These data clearly show the moderating effect of the Civil War on (non-soldierly) ballplaying, and the dramatic "Base Ball Fever" spread of the game to new areas right after the war.

Note: A few Protoballers are venturing to chart the modern game’s earliest growth, from 1843 to 1859. Wish us luck as we try to determine which ones of the reported games were really played by modern rules.